Publications by Ludmilla Steier

2022 roadmap on low temperature electrochemical CO2 reduction

Ming Ma, Sophia Haussener, Ludmilla Steier, Raffaella Buonsanti, Xiaoyan Wang, Etienne Boutin, Xuan Liu

Electrochemical CO2 reduction (CO2R) is an attractive option for storing renewable electricity and for the sustainable production of valuable chemicals and fuels. In this roadmap, we review recent progress in fundamental understanding, catalyst development ...

IOP Publishing Ltd2022

Impact of the Synthesis Route on the Water Oxidation Kinetics of Hematite Photoanodes

Michael Graetzel, Ludmilla Steier

Operando spectroelectrochemical analysis is used to determine the water oxidation reaction kinetics for hematite photoanodes prepared using four different synthetic procedures. While these photoanodes exhibit very different current/voltage performance, the ...

AMER CHEMICAL SOC2020

In situ observation of picosecond polaron self-localisation in alpha-Fe2O3 photoelectrochemical cells

Michael Graetzel, Ludmilla Steier

Hematite (alpha-Fe2O3) is the most studied artificial oxygen-evolving photo-anode and yet its efficiency limitations and their origin remain unknown. A sub-picosecond reorganisation of the hematite structure has been proposed as the mechanism which dictate ...

Springer2019

Low-Temperature Nb-Doped SnO2 Electron-Selective Contact Yields over 20% Efficiency in Planar Perovskite Solar Cells

Shaik Mohammed Zakeeruddin, Ludmilla Steier, Matthew Thomas Mayer, Wolfgang Richard Tress, Jingshan Luo, Juan-Pablo Correa-Baena, Jiyoun Seo, Elham Halvani Anaraki, Silver Hamill Turren Cruz

2018

Analysis of Optical Losses in a Photoelectrochemical Cell: A Tool for Precise Absorptance Estimation

Michael Graetzel, Ludmilla Steier

Optical losses in a photoelectrochemical (PEC) cell account for a substantial part of solar-to-hydrogen conversion losses, but limited attention is paid to the detailed investigation of optical losses in PEC cells. In this work, an optical model of combine ...

Wiley-Blackwell2018

A copper nickel mixed oxide hole selective layer for Au-free transparent cuprous oxide photocathodes

Michael Graetzel, Marcel Roland Schreier, Ludmilla Steier, Matthew Thomas Mayer, Jingshan Luo, Minkyu Son

State-of-the-art cuprous oxide (Cu2O) photocathodes for photoelectrochemical (PEC) water splitting have a long tradition of using gold (Au)-coated F-doped SnO2 (FTO) substrates for the improvement of Cu2O electrodeposition and overall PEC performance. Au i ...

Royal Soc Chemistry2017

Ultrathin Buffer Layers of SnO2 by Atomic Layer Deposition: Perfect Blocking Function and Thermal Stability

Michael Graetzel, Ladislav Kavan, Ludmilla Steier

This study pinpoints the advantages of ultrathin electron 15 selective layers (ESL) of SnO2 fabricated by atomic layer deposition (ALD). These layers recently caught attention in planar perovskite solar cells and appear as powerful alternatives to other ox ...

American Chemical Society2017

Solar conversion of CO2 to CO using Earth-abundant electrocatalysts prepared by atomic layer modification of CuO

Jeremy Luterbacher, Marcel Roland Schreier, Ludmilla Steier, Matthew Thomas Mayer, Jingshan Luo, Florent Emmanuel Héroguel

The solar-driven electrochemical reduction of CO2 to fuels and chemicals provides a promising way for closing the anthropogenic carbon cycle. However, the lack of selective and Earth-abundant catalysts able to achieve the desired transformation reactions i ...

Nature Publishing Group2017

The effect of illumination on the formation of metal halide perovskite films

Michael Graetzel, Ludmilla Steier, Amita Ummadisingu, Wolfgang Richard Tress, Antonio Abate, Jiyoun Seo, Taisuke Matsui

Optimizing the morphology of metal halide perovskite films is an important way to improve the performance of solar cells(1) when these materials are used as light harvesters(2), because film homogeneity is correlated with photovoltaic performance(3). Many ...

Nature Publishing Group2017

Monolithic perovskite/silicon-heterojunction tandem solar cells processed at low temperature

Michael Graetzel, Mohammad Khaja Nazeeruddin, Ulf Anders Hagfeldt, Ludmilla Steier, Juan-Pablo Correa-Baena, Antonio Abate, Michael Saliba

Tandem solar cells combining silicon and perovskite absorbers have the potential to outperform state-of-the-art high efficiency silicon single junction devices. However, the practical fabrication of monolithic silicon/perovskite tandem solar cells is chall ...

Royal Soc Chemistry2016

Highly efficient and stable planar perovskite solar cells by solution-processed tin oxide

Michael Graetzel, Ulf Anders Hagfeldt, Ludmilla Steier, Konrad Domanski, Wolfgang Richard Tress, Juan-Pablo Correa-Baena, Antonio Abate, Taisuke Matsui, Michael Saliba, Elham Halvani Anaraki

Perovskite solar cells (PSCs) are one of the most promising lab-scale technologies to deliver inexpensive solar electricity. Low-temperature planar PSCs are particularly suited for large-scale manufacturing. Here, we propose a simple, solution-processed te ...

Royal Society of Chemistry2016

Fabrication and Characterization of Functional ALD Metal Oxide Thin Films for Solar Applications

Ludmilla Steier

Motivated to revolutionize our today's fossil fuels based energy production, my work concentrated on the investigation of promising low-cost materials for photoelectrochemical hydrogen production and photovoltaic electricity generation. Hydrogen presents a ...

EPFL2016

Highly Efficient and Stable Perovskite Solar Cells based on a Low-Cost Carbon Cloth

Michael Graetzel, Ulf Anders Hagfeldt, Ludmilla Steier, Konrad Domanski, Fabrizio Giordano, Wolfgang Richard Tress, Juan-Pablo Correa-Baena, Antonio Abate, Taisuke Matsui, Michael Saliba

Wiley-VCH Verlag Berlin2016

Cu2O Nanowire Photocathodes for Efficient and Durable Solar Water Splitting

Michael Graetzel, Marcel Roland Schreier, Ludmilla Steier, Matthew Thomas Mayer, Jingshan Luo, Minkyu Son

Due to its abundance, scalability, and nontoxicity, Cu2O has attracted extensive attention toward solar energy conversion, and it is the best performing metal oxide material. Until now, the high efficiency devices are all planar in structure, and their pho ...

American Chemical Society2016

Highly efficient planar perovskite solar cells through band alignment engineering

Michael Graetzel, Mohammad Khaja Nazeeruddin, Shaik Mohammed Zakeeruddin, Ulf Anders Hagfeldt, Ludmilla Steier, Fabrizio Giordano, Wolfgang Richard Tress, Antonio Abate, Taisuke Matsui, Michael Saliba, Tor Jesper Jacobsson

The simplification of perovskite solar cells (PSCs), by replacing the mesoporous electron selective layer (ESL) with a planar one, is advantageous for large-scale manufacturing. PSCs with a planar TiO2 ESL have been demonstrated, but these exhibit unstabil ...

Royal Society of Chemistry2015

Efficient photosynthesis of carbon monoxide from CO2 using perovskite photovoltaics

Michael Graetzel, Shaik Mohammed Zakeeruddin, Marcel Roland Schreier, Ludmilla Steier, Fabrizio Giordano, Matthew Thomas Mayer, Jingshan Luo, Antonio Abate

Artificial photosynthesis, mimicking nature in its efforts to store solar energy, has received considerable attention from the research community. Most of these attempts target the production of H-2 as a fuel and our group recently demonstrated solar-to-hy ...

Nature Publishing Group2015

Low-Temperature Atomic Layer Deposition of Crystalline and Photoactive Ultrathin Hematite Films for Solar Water Splitting

Michael Graetzel, Marcel Roland Schreier, Ludmilla Steier, Matthew Thomas Mayer, Jingshan Luo

We developed a low-temperature atomic layer deposition route to deposit phase pure and crystalline hematite (alpha-Fe2O3) films at 230 degrees C without the need for postannealing. Homogenous and conformal deposition with good aspect ratio coverage was dem ...

American Chemical Society2015

Solution Transformation of Cu2O into CuInS2 for Solar Water Splitting

Michael Graetzel, Marcel Roland Schreier, Stanley David Tilley, Ludmilla Steier, Matthew Thomas Mayer, Jingshan Luo

Though Cu2O has demonstrated high performance as a photocathode for solar water splitting, its band gap is too large for efficient use as the bottom cell in tandem configurations. Accordingly, copper chalcopyrites have recently attracted much attention for ...

American Chemical Society2015

Understanding the Role of Underlayers and Overlayers in Thin Film Hematite Photoanodes

Michael Graetzel, Stanley David Tilley, Ludmilla Steier

Recent research on photoanodes for photoelectrochemical water splitting has introduced the concept of under-and overlayers for the activation of ultrathin hematite films. Their effects on the photocatalytic behavior were clearly shown; however, the mechani ...

Wiley-V C H Verlag Gmbh2014

On the stability enhancement of cuprous oxide water splitting photocathodes by low temperature steam annealing

Michael Graetzel, Stanley David Tilley, Morgan Mertens Stefik, Ludmilla Steier

Given the intermittent nature of solar radiation, the large-scale use of solar energy requires an efficient energy storage solution. So far, the only practical way to store such large amounts of energy is in the form of a chemical energy carrier, i.e., a f ...

Royal Soc Chemistry2014